the activation code does not work

[luisalfo64]

I bought GSX from SinMarket, but the activation code provided doesn't work. It displays an incorrect message.

[virtuali]

You are posting in the MSFS section, so maybe you are trying to activate GSX PRO with a key for GSX (the FSX/P3D version) ? That's the only version sold by Simmarket. If you buy it by mistake, you should contact Simmarket asking for a store credit or a refund, because GSX Pro is only sold here.